JPH0898736A - Head rest device - Google Patents

Abstract

PURPOSE: To provide a head rest device by which the inclination of a head rest body can easily be adjusted. CONSTITUTION: In this head rest device which is provided with a stay 14 supported at an upper part of a seat back, a head rest body supported on the seat back through the stay and a rotation driver to drive and rotate the head rest body by centering a shaft parallel with the direction of the width of a seat, the rotation driver has a cam 19 which has an outer circumference being in contact with the internal wall of the head rest body to press the internal wall of the head rest body so that the head rest body can rotate with respect to the shaft and a motor for driving to rotate the cam.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a headrest device, and more particularly to a headrest device capable of supporting a neck and taking a comfortable posture.

[0002]

2. Description of the Related Art Conventionally, there is known a device in which a neck support for supporting a neck is provided on a headrest body and the neck support is moved to adjust the support of the neck to obtain a comfortable posture.

As a conventional technique of this kind, the technique disclosed in Japanese Utility Model Publication 2-26366 is known. This is to adjust the front-rear position of the headrest body using a motor and a link mechanism.

Secondly, the technique disclosed in Japanese Patent Laid-Open No. 61-253012 is known. In this, a cervical spine support part, which is located in front of the headrest body and is located behind the occupant's neck, is rotatably attached to a side surface of the headrest body by a knob.
The cervical spine support part is fixed by a certain frictional force at the fulcrum of the knob, and is configured to escape backward to prevent damage to the neck part when an impact is applied.

[0005]

In the first prior art, since the headrest body is moved in the front-rear direction via the link mechanism by controlling the drive of the motor, the occupant turns the motor on and off. Adjust the position to your liking by switching or switching the rotation direction. At this time, the rotation speed of the motor is constant, and when the headrest body approaches a position desired by the occupant, the occupant has to bother to turn the motor on or off or switch the rotation direction in detail.

Further, in the second prior art, since the cervical spine support part escapes backward due to the impact.
After that, the occupant had to adjust the headrest body to the desired position again.

A first technical object of the present invention is to provide a headrest device which can easily adjust the inclination of the headrest body. A second technical problem is to provide a headrest device that does not need to be readjusted when an impact is applied.

[0008]

In order to solve the above-mentioned first technical problem, the technical means taken in the invention of claim 1 is a stay supported on an upper part of a seat back, and a seat via the stay. In a headrest device including a headrest main body supported by a back and a rotary drive device that rotationally drives the headrest main body around an axis parallel to the width direction of the seat, the rotary drive device has an outer periphery that abuts an inner wall of the headrest main body. And a motor for pressing the inner wall of the headrest main body so that the headrest main body can rotate about an axis and a motor for rotationally driving the cam.

In order to solve the second technical problem as well, the technical means taken in the invention of claim 2 is to arrange the cam above the shaft and below the shaft so as to fix the occupant's neck. A cervical spine support portion located behind and a biasing means for biasing the inner wall of the headrest main body in the direction of abutting the outer circumference of the cam.

[0010]

According to the present invention, when the motor is driven to rotate the cam, the outer periphery of the cam presses the inner wall of the headrest body, and the headrest body is centered on an axis parallel to the width direction of the seat. It is driven to rotate. Therefore, the speed at which the headrest body is rotationally driven can be changed by freely setting the shape of the outer circumference of the cam, and
The headrest main body can be rotationally driven in the forward direction and the reverse direction without the occupant switching the rotational direction of the motor.

According to the second aspect of the present invention, when an impact is applied, the head of the occupant falls rearward, and at this time, the cervical spine support portion is pressed, and the headrest main body pivots against the urging force of the urging means. The cervical spine support part is rotated in the direction of retracting backward about the center to prevent the neck from being damaged. And
When the body of the occupant is returned to the normal position, the pressing force on the cervical spine support part disappears, and the headrest body returns to the state before the impact of the inner wall abutting the outer periphery of the cam due to the urging force of the urging means. .

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described with reference to the drawings.

FIG. 1 is an assembly view of the headrest body of this embodiment, FIG. 2 is a front view of the headrest body of this embodiment, and FIG.
Is a plan view of the headrest body of this embodiment (the bracket is omitted), FIG. 4 is a side view of the headrest body of this embodiment,
FIG. 5 is a plan view of the cam of this embodiment.

As shown in the figure, the headrest body 1
Reference numeral 0 is composed of first and second brackets 11 and 12, both of which are integrally connected by a screw 13. First
Below the horizontal axis 14a of the stay 14 of the bracket 11, the cervical spine support portion 11b located behind the neck of the occupant.
Are formed. First and second brackets 11, 12
The openings 11a and 12a are formed in the side surface of the headrest body 10. The opening 11a has an L shape, while the opening 12a has an elongated shape, and as shown in FIG. 4, the horizontal shaft 14a of the stay 14 is held so as to be sandwiched at the position where the openings overlap. . Vertical axes 14b and 14c of the stay 14 are held by a seat back (not shown).

The headrest body 10 can be driven to rotate with respect to the horizontal shaft 14a of the stay 14, which is a shaft, by a rotary drive device described later. This rotary drive device includes a stay 1
4, a motor bracket 15 having a U-shaped cross section held by the horizontal shaft 14a, and a reduction mechanism (not shown) internally fixed to the motor bracket 15 with screws 16 and interlocked with a motor (not shown) and an output shaft of the motor ( (Not shown), a drive source 17 and a drive source 1 from a motor via a speed reduction mechanism.
7, a cam 19 locked to the tip of the output rotary shaft 17a protruding from the housing so as to be integrally rotatable with the output rotary shaft 17a and a screw 18, a first bracket 11 at one end and a motor bracket 15 at the other end. The main body 10 is constituted by a spring 20 which is an urging means for urging the inner wall of the main body 10 against the outer periphery of the cam 19. As can be seen from FIG. 2, the cam 19 is provided on the horizontal axis 14 of the stay 14.
It is arranged above a.

Next, the operation of this embodiment will be described.

When an occupant turns on a motor drive switch (not shown), the motor is rotationally driven and the rotary output shaft 17a rotates via the speed reduction mechanism. When the rotation output shaft 17a rotates, the cam 19 is integrally driven to rotate, and the bracket 11 is pressed in association with the change in the distance from the rotation center of the cam 19 to the outer peripheral surface. The pressing force of the cam 19 resists the urging force of the spring 20 and causes the headrest main body 10 to move as shown in FIG.
It is driven to rotate from the position shown by the solid line to the position shown by the chain double-dashed line.

In the present embodiment, the speed at which the headrest body 10 is rotationally driven can be changed by freely setting the shape of the outer periphery of the cam, and the headrest can be operated without the occupant switching the rotation direction of the motor. Since the main body 10 can be rotationally driven in the forward and reverse directions, a troublesome operation is unnecessary.

Further, according to the present invention, when an impact is applied, the head of the occupant falls rearward, and at this time, the cervical spine support portion 11b is pressed and the headrest body 10 stays against the biasing force of the spring 20. The cervical spine support portion 11b is rotated around the horizontal axis 14a of 14 in the direction of receding backward to prevent damage to the neck portion (moved from the two-dot chain line in FIG. 6 to the position indicated by the solid line). Then, when the body of the occupant is returned to the normal position, the pressing force on the cervical spine support portion 11b disappears and the urging force of the spring 20 causes the headrest body 10
Since the inner wall returns to the state before the impact that the inner wall abuts on the outer periphery of the cam, the readjustment of the cervical spine support portion 11b after the impact is unnecessary.

[0020]

According to the first aspect of the invention, the speed at which the headrest main body is rotationally driven can be changed by freely setting the outer peripheral shape of the motor cam, and the occupant does not switch the rotational direction of the motor. However, since the headrest body can be rotationally driven in the forward and reverse directions, a troublesome operation is unnecessary.

According to the second aspect of the present invention, when an impact is applied, the head of the occupant falls backward, and at this time, the cervical spine support portion is pressed to resist the urging force of the urging means so that the headrest main body pivots. The cervical spine support part is rotated in the direction of retracting backward about the center to prevent the neck from being damaged. Then, when the body of the occupant is returned to the normal position, the pressing force to the cervical spine support part disappears and the headrest body returns to the state before the impact of the inner wall abutting the outer periphery of the cam is applied by the urging force of the urging means. Therefore, it is not necessary to readjust the cervical spine support after the impact is applied.

[Brief description of drawings]

FIG. 1 shows an assembly view of a headrest body according to the present invention.

FIG. 2 shows a front view of a headrest body according to the present invention.

FIG. 3 shows a plan view of a headrest body according to the present invention (a bracket is omitted).

FIG. 4 shows a side view of the headrest body according to the invention.

FIG. 5 shows a cam of a rotary drive unit used in the headrest body according to the present invention.

FIG. 6 shows an explanatory view of the operation of the headrest body according to the present invention.

[Explanation of symbols]

 10 ... Headrest main body 11b ... Cervical spine support part 14 ... Stay 14a ... Stay horizontal axis (axis) 17 ... Drive source 19 ... Cam 20 ... Spring (biasing means)

Claims (2)

[Claims] 1. A stay supported on the upper part of a seat back, a headrest main body supported by the seat back via the stay, and the headrest main body is rotationally driven about an axis parallel to the width direction of the seat. In a headrest device provided with a rotation drive device, the rotation drive device has an outer periphery that abuts an inner wall of the headrest body, and has an inner wall of the headrest body so that the headrest body is rotatable with respect to the shaft. A headrest device comprising a pressing cam and a motor for rotationally driving the cam. 2. The cervical spine support portion, which is disposed below the shaft and is located below the shaft and behind the neck of an occupant, and the inner wall of the headrest body, and the outer circumference of the cam. A headrest device, comprising: a biasing unit that biases in a direction to bring the headrest into contact with the headrest device.